1. Field of the Invention:
The invention relates to a process for manufacturing a magnesium carbonate board. More particularly, the invention relates to a process for manufacturing a magnesium carbonate board which is useful as building material.
2. Description of the Prior Art:
Hitherto the process for manufacturing a magnesium carbonate board consisted of preparing a neutral magnesium carbonate aqueous suspension by blowing gaseous carbon dioxide into an aqueous suspension of magnesium hydroxide, mixing the resulting neutral magnesium carbonate aqueous suspension with fibrous material and the like, casting the resulting mixed suspension onto a porous carrier to form a layer thereon through dehydration, laminating a number of said layers and pressing and heat curing the laminating layers. In such a process, a part of the neutral magnesium carbonate is changed into the bosic magnesium carbonate during the curing operation and gaseous carbon dioxide is formed. Formation of gaseous carbon dioxide makes a magnesium carbonate which is very porous. Conventional magnesium carbonate board has a specific gravity, below 0.85 low hardness and low flexural rigidity.